SELECT
e.name AS name,
s.total_amount AS total_amount
FROM employees e
JOIN (
SELECT
o.employee_id,
SUM(o.amount) AS total_amount
FROM orders o
GROUP BY o.employee_id
) s ON s.employee_id = e.id
WHERE s.total_amount > (
SELECT AVG(s2.total_amount)
FROM (
SELECT
o2.employee_id,
SUM(o2.amount) AS total_amount
FROM orders o2
GROUP BY o2.employee_id
) s2
JOIN employees e2 ON e2.id = s2.employee_id
WHERE e2.department_id = e.department_id
);